A system for preventing corrosion of a bag-type dust collector under high humidity conditions in a dry-wet coke quenching and dust removal high humidity condition
By adding a return air system and a calcium oxide treatment system, the airflow distribution in the corners of the ash hopper is improved and the dew point temperature is increased, which solves the corrosion problem of bag filters under high humidity conditions, extends the equipment life and reduces maintenance costs.
Patent Information
- Application Number
- CN202521841836.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-28
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-08-28
AI Technical Summary
When baghouse dust collectors are used to process flue gas from wet quenching systems or mixed wet and dry quenching systems, they are prone to corrosion due to water vapor condensation in the corner areas of the ash hopper. This results in a short equipment lifespan, affects production continuity, and increases maintenance costs.
An additional return air system and a calcium oxide treatment system are added. By improving the airflow distribution in the corners of the ash silo and utilizing the moisture absorption and heat release properties of calcium oxide to increase the dew point temperature, the return air volume and calcium oxide delivery volume are adjusted in real time by a humidity sensor to prevent corrosion.
It effectively extends the service life of baghouse dust collectors, reduces maintenance costs, and solves the problem of condensation and corrosion in the corners of ash silos.
Smart Images
Figure CN224678002U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of coke quenching and dust removal technology, specifically relating to a system for preventing corrosion of bag filters under high humidity conditions in dry and wet coke quenching and dust removal. Background Technology
[0002] With increasingly stringent environmental protection policies in my country, the country has raised its requirements for flue gas emission control. In order to meet the increasingly stringent emission requirements, coking enterprises across the country have implemented large-scale flue gas purification system renovation projects in recent years, and have generally added high-efficiency dust removal systems.
[0003] However, during actual system operation, it was found that when the bag filter handles flue gas from wet quenching systems or mixed wet and dry quenching systems, the flue gas contains a large amount of water vapor. In winter or cold regions, if the outdoor temperature drops sharply below the dew point, the water vapor easily condenses into liquid water in vortex areas such as corners of the dust collector's ash hopper and dead corners of flue gas flow. The liquid water reacts with the acidic gases in the flue gas, thus corroding the bag filter. This reduces the lifespan of the bag filter to only 1-2 years, seriously affecting production continuity and significantly increasing maintenance costs.
[0004] Therefore, it is crucial to address the issue of easy corrosion in the corner areas of the dust collector's ash hopper when using a wet quenching system or a combined wet and dry quenching dust removal system in coking production. Utility Model Content
[0005] Based on the above-mentioned technical problems, the purpose of this utility model is to provide a system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal. This system improves the airflow distribution in the corner area of the ash silo by adding a return air system and a calcium oxide treatment system, and increases the dew point temperature of the local environment by utilizing the moisture absorption and heat release properties of calcium oxide, thereby fundamentally solving the problem of condensation corrosion in the corner of the ash silo and extending its service life.
[0006] The specific technical solution is as follows: A system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal includes: a dust removal system, a return air system, a calcium oxide treatment system, and a humidity sensor; the dust removal system includes a baghouse dust collector, a dust collector fan, and an exhaust stack, which are connected sequentially; the return air system includes a return air duct, a return air fan, a first electric regulating valve, and a nozzle, one end of which is connected to the connecting pipe between the dust collector fan and the exhaust stack, and the other end of which is connected to the ash hopper of the baghouse dust collector through the nozzle, and the return air fan and the first electric regulating valve are connected to the exhaust stack. All electric regulating valves are installed on the return air duct; the calcium oxide treatment system includes a calcium oxide silo, a Roots blower, a calcium oxide conveying pipeline, a calcium oxide conveying bypass pipeline, and a second electric regulating valve. The calcium oxide conveying pipeline is connected to the calcium oxide silo and the desulfurization flue gas pipeline of the plant's desulfurization system, and the Roots blower is connected to the calcium oxide conveying pipeline; both ends of the calcium oxide conveying bypass pipeline are connected to the calcium oxide conveying pipeline and the return air duct, and the second electric regulating valve is installed on the calcium oxide conveying bypass pipeline; the humidity sensor is installed on one side of the bag filter.
[0007] In addition, the system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal provided by this utility model may also have the following additional technical features: In the above technical solution, a gate valve is installed on the return air duct, and the gate valve is located in front of the return air fan.
[0008] In the above technical solution, the sensor is interlocked with the first electric regulating valve and the second electric regulating valve.
[0009] In the above technical solution, a hopper pump is installed at the ash discharge port of the bottom ash hopper of the bag filter. The input end of the hopper pump is connected to the first compressed air storage tank, and the output end of the hopper pump is connected to the pneumatic conveying pipeline, which is also connected to the dust storage hopper.
[0010] In the above technical solution, a humidifier is installed at the bottom of the dust storage silo.
[0011] In the above technical solution, the nozzle is set on the side wall of the bag filter and is opposite to the corner of the ash hopper.
[0012] The above technical solution also includes: a second compressed air storage tank, which is connected to the bag filter and is used to perform jet blowing operation on the filter bags inside the bag filter.
[0013] This utility model discloses a system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal. Compared with the prior art, the advantages are as follows: 1. By utilizing the positive pressure of the existing dust collector fan and combining it with the added return air system, part of the gas in the connecting pipe between the dust collector fan and the exhaust stack is circulated back to the bag filter, optimizing the airflow distribution in the corners of the ash silo and reducing the impact of condensation corrosion in the corners of the ash silo. Furthermore, by adding a calcium oxide treatment system, the dew point temperature of the local environment is increased by utilizing the moisture absorption and heat release properties of calcium oxide, thereby fundamentally solving the problem of condensation corrosion in the corners of the ash silo and extending its service life.
[0014] 2. The humidity sensor monitors the humidity in the silo corner in real time and links the first and second electric regulating valves to enable the system to adjust the return air volume and calcium oxide delivery volume according to the different humidity values measured.
[0015] 3. By adding a gate valve in front of the return air fan, it is easier to inspect and maintain the return air fan. Attached Figure Description
[0016] Figure 1 This is a flowchart of a system for preventing corrosion of a bag filter under high humidity conditions in dry and wet quenching dust removal according to this utility model. Figure 2 This is a top view of the bag filter of this utility model; in, Figures 1 to 2 The correspondence between the reference numerals and component names in the attached drawings is as follows: 10 Baghouse dust collector, 11 Dust collector fan, 12 Exhaust stack, 13 Return air duct, 14 Return air fan, 15 First electric regulating valve, 16 Nozzle, 17 Calcium oxide silo, 18 Roots blower, 19 Calcium oxide conveying pipeline, 20 Calcium oxide conveying bypass pipeline, 21 Second electric regulating valve, 22 Humidity sensor, 23 Slide valve, 24 Silo pump, 25 First compressed air storage tank, 26 Pneumatic conveying pipeline, 27 Dust storage silo, 28 Humidifier, 29 Second compressed air storage tank. Detailed Implementation
[0017] The following are specific implementation cases and appendices. Figure 1-2 The present invention will be further described below, but the present invention is not limited to these embodiments.
[0018] A system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal operations, such as... Figure 1-2As shown, the system includes: a dust removal system, a return air system, a calcium oxide treatment system, and a humidity sensor 22. The dust removal system includes a bag filter 10, a dust removal fan 11, and an exhaust stack 12, which are connected in sequence. The return air system includes a return air duct 13, a return air fan 14, a first electric regulating valve 15, and a nozzle 16. One end of the return air duct 13 is connected to the connecting pipe between the dust removal fan 11 and the exhaust stack 12, and the other end of the return air duct 13 is connected to the ash hopper of the bag filter 10 through the nozzle 16. The return air fan 14 and the first electric regulating valve 15 are both located in... The calcium oxide treatment system includes a calcium oxide silo 17, a Roots blower 18, a calcium oxide conveying pipeline 19, a calcium oxide conveying bypass pipeline 20, and a second electric regulating valve 21. The calcium oxide conveying pipeline 19 is connected to the calcium oxide silo 17 and the desulfurization flue gas pipeline of the plant's desulfurization system, and the Roots blower 18 is connected to the calcium oxide conveying pipeline 19. The two ends of the calcium oxide conveying bypass pipeline 20 are connected to the calcium oxide conveying pipeline 19 and the return air duct 13, respectively, and the second electric regulating valve 21 is installed on the calcium oxide conveying bypass pipeline 20. The humidity sensor 22 is installed on one side of the bag filter 10.
[0019] By adopting the above structure, by utilizing the positive pressure of the original dust removal fan 11 and combining it with the added return air system, the negative pressure of the return air fan 14 is used to extract a portion of the flue gas from the positive pressure section of the dust removal fan 11 and send it to the nozzle 16, and then spray it towards the corner of the ash hopper of the bag filter 10, thereby improving the airflow distribution in the corner of the ash hopper and reducing the impact of condensation corrosion on the corner of the ash hopper. By using the Roots blower 18 to send powdered calcium oxide to the return air duct 13, and then using the positive pressure of the return air blower 14 to send the calcium oxide powder to the nozzle 16, it reacts with the water vapor in the high humidity flue gas at the corner of the ash hopper, thereby reducing the relative humidity of the flue gas. The reaction between calcium oxide and water releases a large amount of heat, which can raise the local temperature at the corner of the bag filter 10, thus fundamentally solving the problem of condensation and corrosion at the corner of the ash hopper and extending its service life.
[0020] Specifically, the calcium oxide powder is directly mixed with the gas in the return air duct 13 after the first electric regulating valve 15. Compared with mixing before the nozzle 16, this can reduce the head of the Roots blower 18. Furthermore, the calcium oxide powder reacts with the water vapor in the return air duct 13, which can increase the temperature of the return air and is more conducive to solving the problem of corner corrosion in the ash hopper of the bag filter 10.
[0021] Specifically, by utilizing the return air of the positive pressure section of the dust removal fan 11 to optimize the airflow distribution in the corner area of the ash hopper of the bag filter 10, and by using the existing calcium oxide hopper 17 of the environmental dust removal ground station to treat the water vapor in the corner area of the ash hopper, the system's existing equipment resources are fully utilized, eliminating the need to build new hoppers and flue gas treatment equipment, thus achieving the secondary utilization of dust removal flue gas.
[0022] Specifically, the calcium oxide processing system is also equipped with a silencer and a rotary feeder. Specifically, compressed air can be drawn from a nearby air source to help blow the calcium oxide delivery pipe 19, thereby preventing the calcium oxide delivery pipe 19 from becoming blocked.
[0023] In an embodiment of this utility model, a slide gate valve 23 is provided on the return air duct 13, and the slide gate valve 23 is located in front of the return air fan 14.
[0024] By adding a gate valve 23 in front of the return air fan 14, it is easier to inspect and maintain the return air fan 14.
[0025] In an embodiment of this utility model, the sensor is interlocked with the first electric regulating valve 15 and the second electric regulating valve 21.
[0026] The humidity sensor 22 monitors the humidity in the silo corner in real time and links the first electric regulating valve 15 and the second electric regulating valve 21 to enable the system to adjust the return air volume and calcium oxide delivery volume according to the different humidity values measured.
[0027] Specifically, the control modes of the first electric regulating valve 15 and the second electric regulating valve 21 have the following four operating conditions: Operating condition a: When the relative humidity of the flue gas measured by the humidity sensor 22 at the corner of the ash hopper of the bag filter 10 is lower than 70%, the first electric regulating valve 15 ensures a minimum opening of 50%, and the second electric valve is closed to improve the airflow organization at the corner of the hopper. Operating condition b. When the relative humidity of the flue gas measured by the humidity sensor 22 at the corner of the ash hopper of the bag filter 10 reaches 70%, the opening degree of the first electric regulating valve 15 and the second electric regulating valve 21 is adjusted to 70%. Operating condition c. When the relative humidity of the flue gas measured by the humidity sensor 22 at the corner of the ash hopper of the bag filter 10 reaches 85%, the opening degree of the first electric regulating valve 15 and the second electric regulating valve 21 is adjusted to 85%. Operating condition d. When the relative humidity of the flue gas measured by the humidity sensor 22 at the corner of the ash hopper of the bag filter 10 reaches 95%, the opening degree of the first electric regulating valve 15 and the second electric regulating valve 21 is adjusted to 100%. To avoid frequent switching between operating conditions, the operating condition is switched only after a 20-second delay when the corresponding conditions are continuously met.
[0028] In an embodiment of this utility model, a hopper pump 24 is provided at the ash discharge port of the bottom ash hopper of the bag dust collector 10. The input end of the hopper pump 24 is connected to the first compressed air storage tank 25, and the output end of the hopper pump 24 is connected to the pneumatic conveying pipeline 26, which is connected to the dust storage hopper 27.
[0029] The calcium hydroxide generated by the reaction of calcium oxide and water in the bag filter 10 can directly react with sulfur dioxide in the flue gas, and the resulting calcium sulfate and calcium sulfite are transported to the dust storage silo 27 by the silo pump 24.
[0030] In an embodiment of this utility model, a humidifier 28 is provided at the bottom of the dust storage bin 27.
[0031] The dust discharged from the dust storage bin 27 is humidified by the humidifier 28.
[0032] In an embodiment of this utility model, the nozzle 16 is disposed on the side wall of the bag filter 10 and is opposite to the corner of the ash hopper.
[0033] In an embodiment of this utility model, it further includes: a second compressed air storage tank 29, which is connected to the bag filter 10 and is used to perform a blowing operation on the filter bags inside the bag filter 10.
[0034] By spraying compressed air from the second compressed air tank 29 onto the filter bag, the purpose of periodically cleaning the filter bag is achieved, thus avoiding excessive dust accumulation on the surface of the filter bag and causing blockage.
[0035] Implementation process: By utilizing the negative pressure of the return air fan 14, a portion of the flue gas from the positive pressure section of the dust collector fan 11 is extracted and sent to the nozzle 16 under the positive pressure of the dust collector fan 11. The gas is then sprayed onto the corner of the ash hopper of the bag filter 10, thereby improving the airflow distribution in the corner of the ash hopper and preventing eddy formation. By utilizing the positive pressure of the Roots blower 18, powdered calcium oxide is sent to the return air duct 13. Then, the positive pressure of the return air fan 14 sends the calcium oxide powder to the nozzle 16, where it reacts with the water vapor in the high-humidity flue gas at the corner of the ash hopper, thereby reducing the relative humidity of the flue gas. The reaction between calcium oxide and water releases a large amount of heat, which can raise the local temperature at the corner of the bag filter 10, thus fundamentally solving the problem of condensation and corrosion at the corner of the ash hopper and extending its service life.
[0036] In the description of this utility model, the term "multiple" refers to two or more. Unless otherwise explicitly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.
[0037] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, characterized in that, include: Dust removal system, return air system, calcium oxide treatment system, and humidity sensor; The dust removal system includes a bag filter, a dust removal fan, and an exhaust stack, which are connected in sequence. The return air system includes a return air duct, a return air fan, a first electric regulating valve, and nozzles. One end of the return air duct is connected to the connecting pipe between the dust removal fan and the exhaust stack, and the other end of the return air duct is connected to the ash hopper of the bag filter through the nozzles. The return air fan and the first electric regulating valve are both installed on the return air duct. The calcium oxide treatment system includes a calcium oxide silo, a Roots blower, a calcium oxide conveying pipeline, a calcium oxide conveying bypass pipeline, and a second electric regulating valve. The calcium oxide conveying pipeline is connected to the calcium oxide silo and the desulfurization flue gas pipeline of the plant's desulfurization system, respectively, and the Roots blower is connected to the calcium oxide conveying pipeline. The two ends of the calcium oxide conveying bypass pipeline are connected to the calcium oxide conveying pipeline and the return air pipeline, respectively, and the second electric regulating valve is installed on the calcium oxide conveying bypass pipeline. The humidity sensor is located on one side of the bag filter.
2. The system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, as described in claim 1, is characterized in that... The return air duct is equipped with a gate valve, and the gate valve is located in front of the return air fan.
3. The system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, as described in claim 1, is characterized in that... The sensor is interlocked with the first electric regulating valve and the second electric regulating valve.
4. The system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, as described in claim 1, is characterized in that... The bottom ash hopper of the bag filter is equipped with a hopper pump. The input end of the hopper pump is connected to the first compressed air storage tank, and the output end of the hopper pump is connected to the pneumatic conveying pipeline, which is connected to the dust storage hopper.
5. The system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, as described in claim 4, is characterized in that... A humidifier is installed at the bottom of the dust storage silo.
6. The system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, as described in claim 1, is characterized in that... The nozzle is located on the side wall of the bag filter and is opposite to the corner of the ash hopper.
7. The system for preventing corrosion of baghouse dust collectors under high humidity conditions in dry and wet quenching dust removal, as described in claim 1, is characterized in that... Also includes: The second compressed air storage tank is connected to the bag filter and is used to perform jet cleaning of the filter bags inside the bag filter.